1. Technical Field
The present invention generally relates to touch sensing technology, and more particularly to a touch sensing structure for a capacitive touch panel and a method for making the structure.
2. Description of the Background
In recent years, the touch panel gets more and more popular, and has the tendency to replace the mouse and keyboard in the future. Touch panels have been widely used in many electronic devices to enable users to input data. Now, a touch panel is always integrated with a display panel, so the users can select an operation by directly touching the corresponding images shown on the display panel. Therefore, such a combined structure of the touch panel and the display panel provides users with better portability and more comfortable input operation.
There are many types of touch panels, such as resistance touch panel, capacitive touch panel, infrared sensing touch panel, electromagnetic sensing touch panel, and acoustic wave sensing touch panel, according to different technology principles. Herein, the capacitive touch panel is a comparatively better type because of its high sensitivity, low cost, and simple structure. Theoretically, the capacitive touch panel determines the touch position by detecting the capacitance changes of the electrodes caused by the touch of human body or other grounded material.
Referring to FIG. 1, a conventional capacitive touch panel has x-axis (X0-X7) and Y-axis (Y0-Y4) electrode strips. In operation, a control circuit scans the electrode strips sequentially. When a human finger or other grounded conductors touch a point (shown as black area) of the capacitive touch panel, the capacitance of the X-axis electrode strips and Y-axis electrode strips being touched changes, and after sensing the capacitance of the electrode strips, the control circuit will determine the X-axis and Y-axis coordinates of the touched position based on the capacitance change.
Referring to FIG. 2, a touch sensing structure for capacitive touch panel is shown. The touch sensing structure 10 includes a plurality of first electrode units 11, a plurality of second electrode units 12, a plurality of first conductive lines 111, a plurality of second conductive lines 112, and a plurality of insulators 13 disposed between the first conductive lines 111 and the second conductive lines 112. The first electrode units 11 and the second electrode units 12 are formed on the substrate 1. Each first conductive line 111 is used for interconnecting adjacent first electrode units 11 and each second conductive line 112 is used for interconnecting adjacent second electrode units 12. Each insulator 13 is formed between a first conductive line 111 and a corresponding second conductive line 112 to make the first conductive line 111 electrically insulated from the second conductive line 112.
Referring to FIG. 3, a side view of the touch sensing structure 10 of FIG. 2 is shown. Because of the disposition of the insulators 13, there are many protrusions of the touch sensing structure. Therefore reflection and refraction of light are easily caused by the protrusions and the visibility of the first conductive line 111 is increased. Consequently, the light transmittance of the touch sensing structure can not be enhanced. Furthermore, because the first conductive lines 111 bestride the insulators, the first conductive lines 111 are easy to breakdown under external forces.
Therefore, a new touch sensing structure not only having a comparatively high light transmittance but also a comparatively high rigidity is needed to overcome said shortcomings.